Ricciocarpos natans (Marchantiophyta, Ricciaceae), nueva para Costa Rica, con una revisión de su presencia en América Latina

Background and Aims: Ricciocarpos natans is one of the few species of truly aquatic hepatics. It has a subcosmopolitan distribution and appears to be more common in temperate areas. The species has been considered to be very rare in Central America where it was known only from Panama. The objective of this study is to report the presence of this species in Costa Rica and to survey its current distribution in Latin America. Methods: We provide an overview of the distribution of the floating aquatic liverwort Ricciocarpos natans in Latin America based on literature, herbarium specimens and unequivocal photographic records across the region, as well as field work in Costa Rica. Key results: Ricciocarpos natans is reported as new for Costa Rica. We provide the most complete survey to date of the geographic distribution of the species in Latin America. Conclusions: Our survey shows that Ricciocarpos natans appears to be more common and widely distributed in the Neotropics than previously assumed. Its assumed rarity seems to be the result of insufficient collection efforts.Antecedentes y Objetivos: Ricciocarpos natans es una de las pocas especies de hepáticas verdaderamente acuáticas. Tiene una distribución subcosmopolita y parece ser más común en áreas templadas. La especie ha sido considerada muy rara en América Central, donde solo se conocía de Panamá. El objetivo de este estudio es reportar la presencia de esta especie en Costa Rica y revisar su distribución en América Latina.Métodos: Brindamos una descripción general de la distribución de la hepática acuática flotante Ricciocarpos natans en América Latina con base en la literatura, especímenes de herbario y registros fotográficos inequívocos en toda la región, así como trabajo de campo en Costa Rica.Resultados clave: Ricciocarpos natans se reporta como nueva para Costa Rica. Brindamos el estudio más completo hasta la fecha de la distribución geográfica de la especie en América Latina.Conclusiones: Nuestro estudio muestra que Ricciocarpos natans parece ser más común y más ampliamente distribuida en el Neotrópico de lo que se suponía anteriormente. Su supuesta rareza parece ser el resultado de esfuerzos de recolección insuficientes

Infrared-excess white dwarfs in the Gaia 100 pc sample

We analyse the 100¿pc Gaia white dwarf volume-limited sample by means of VOSA (Virtual Observatory SED Analyser) with the aim of identifying candidates for displaying infrared excesses. Our search focuses on the study of the spectral energy distribution (SED) of 3733 white dwarfs with reliable infrared photometry and GBP - GRP colours below 0.8 mag, a sample that seems to be nearly representative of the overall white dwarf population. Our search results in 77 selected candidates, 52 of which are new identifications. For each target, we apply a two-component SED fitting implemented in VOSA to derive the effective temperatures of both the white dwarf and the object causing the excess. We calculate a fraction of infrared-excess white dwarfs due to the presence of a circumstellar disc of 1.6 ± 0.2 per¿cent, a value that increases to 2.6 ± 0.3 per¿cent if we take into account incompleteness issues. Our results are in agreement with the drop in the percentage of infrared excess detections for cool (20¿000¿K) white dwarfs obtained in previous analyses. The fraction of white dwarfs with brown dwarf companions we derive is ¿0.1–0.2 per¿cent.Peer ReviewedPostprint (author's final draft

Análisis de producciones y rendimientos del sistema de resinación de pica de corteza con estimulación química de doble cara ancha en masas de Pinus pinaster Ait. cuyo objetivo principal es la producción de madera

El aprovechamiento resinero se está posicionando en los últimos años en el noroeste peninsular como una posibilidad para generar ingresos complementarios en los pinares atlánticos productores de madera. No obstante, las condiciones del monte gallego (atomización de la propiedad, pendiente, presencia de matorral y altas densidades) implican rendimientos y costes diferentes a los pinares que se resinan fundamentalmente en Castilla y León. Por lo tanto, es necesario conocer tanto las producciones de miera o resina como los rendimientos que supone su extracción en estas circunstancias. En el presente estudio se analizan las producciones para el método de resinación de pica de corteza, para pinares próximos a la edad de corta y cuyo aprovechamiento principal es la madera. Se estudió la producción para una cara de 12 cm de ancho, que es lo habitual en España, para una cara de 16 cm, para dos caras de 12 cm y para dos caras de 16 cm. También se analizaron los tiempos y rendimientos para el sistema más productor, que fue el de dos caras de 16 cm

Spectral classification of the 100 pc white dwarf population from Gaia-DR3 and the virtual observatory

The third data release of Gaia has provided low resolution spectra for 100 000 white dwarfs (WDs) that, together with the excellent photometry and astrometry, represent an unrivalled benchmark for the study of this population. In this work, we first built a highly-complete volume-limited sample consisting in 12 718 WDs within 100 pc from the Sun. The use of VOSA tool allowed us to perform an automated fitting of their spectral energy distributions to different atmospheric models. In particular, the use of spectrally derived J-PAS photometry from Gaia spectra led to the classification of DA and non-DA WDs with an accuracy ¡ 90%, tested in already spectroscopically labelled objects. The excellent performance achieved was extended to practically the whole population of WDs with effective temperatures above 5500 K. Our results show that, while the A branch of the Gaia WD Hertzsprung-Russell diagram is practically populated by DA WDs, the B branch is largely formed by non-DAs (65%). The remaining 35% of DAs within the B branch implies a second peak at 0.8 M in the DA- mass distribution. Additionally, the Q branch and its extension to lower temperatures can be observed for both DA and non-DA objects due to core crystallisation. Finally, we derived a detailed spectral evolution function, which confirms a slow increase of the fraction of non-DAs as the effective temperature decreases down to 10 500 K, where it reaches a maximum of 36% and then decreases for lower temperatures down to 31%We are greatly indebted to Detlev Koester for providing us with his white dwarf model atmosphere spectra. ST acknowledges fruitful discussion and data provided by Carlos López-Sanjuan. We also thank to the referee Dr Jay Holberg for his valuable comments. FJE acknowledges financial support from the Servicio P ¨ublico de Empleo Estatal, Spain. PC acknowledges financial support from the Government of Comunidad Autónoma de Madrid (Spain) via postdoctoral grant ‘Atracción de Talento Investigador’ 2019-T2/TIC-14760. ST and ARM acknowledge support from MINECO under the PID2020-117252GB-I00 grant. ARM acknowledges support from Grant RYC-2016-20254 funded by MCIN/AEI/10.13039/501100011033 and by ESF Investing in your future. RMO is funded by INTA through grant PRE- OBSERVATORIO. MEC acknowledges support from NASA grants (HGC) 80NSSC17K0008 and (LWS) 80NSSC20K0193 and the University of Colorado Boulder.Peer ReviewedPostprint (published version

White dwarf-main-sequence binaries from Gaia EDR3: The unresolved 100 pc volume-limited sample

We use the data provided by the Gaia Early Data Release 3 to search for a highly-complete volume-limited sample of unresolved binaries consisting of a white dwarf and a main sequence companion (i.e. WDMS binaries) within 100 pc. We select 112 objects based on their location within the Hertzsprung-Russell diagram, of which 97 are new identifications. We fit their spectral energy distributions (SED) with a two-body fitting algorithm implemented in VOSA (Virtual Observatory SED Analyser) to derive the effective temperatures, luminosities and radii (hence surface gravities and masses) of both componentsARM acknowledges financial support from the MINECO under the Ramón y Cajal program (RYC-2016-20254). ST and ARM acknowledge support from the MINECO under the AYA2017-86274-P grant, and the AGAUR grant SGR-661/2017. ESM and FJE acknowledge financial support from the MINECO under the AYA2017-86274-P grant. FJE acknowledges support from the H2020 ESCAPE project (Grant Agreement no. 824064). LMC, LGA and AHC acknowledge support from AGENCIA through the Programa de Modernización Tecnológica BID 1728/OC-AR, and from CONICET through the PIP 2017-2019 GI grant. This publication makes use of VOSA and SVO DiscTool, developed under the Spanish Virtual Observatory project supported from the Spanish MINECO through grant AyA2017-84089. This research has made use of Aladin sky atlas developed at CDS, Strasbourg Observatory, France (Bonnarel et al. 2000; Boch & Fernique 2014). TOPCAT (Taylor 2005) and STILTS (Taylor 2006) have also been widely used in this paper. We thank the anonymous referee for the helpful suggestions. The authors are greatly indebted to Detlev Koester for sharing his grid of model atmosphere white dwarf spectra. The authors also thank Roberto Raddi for sharing the grid of white dwarf absolute magnitudes calculated for the Gaia EDR3 bandpasses. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/ gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/ consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral AgreementPostprint (updated version

The Milk Microbiota of the Spanish Churra Sheep Breed: New Insights into the Complexity of the Milk Microbiome of Dairy Species

Artículo de Investigación científicaMilk from healthy animals has classically been considered a sterile fluid. With the development of massively parallel sequencing and its application to the study of the microbiome of different body fluids, milk microbiota has been documented in several animal species. In this study, the main objective of this work was to access bacterial profiles of healthy milk samples using the next-generation sequencing of amplicons from the 16S rRNA gene to characterise the milk microbiome of the Churra breed. A total of 212 samples were collected from two Churra dairy farms with a different management system. The core milk microbiota in Churra ewes includes lesser genera (only two taxa: Staphylococcus and Escherichia/Shigella) than studies reported in other dairy species or even in a previous study in Assaf sheep milk. We found that diversity values in the two flocks of Churra breed were lower than the diversity of the milk microbiota in Assaf. The non-metric multidimensional scaling (NMDS) ordination using Bray-Curtis distance separates samples based on their microbiota composition. The information reported here might be used to understand the complex issue of milk microbiota composition.S

Sporadic cloud-based mobile augmentation on the top of a virtualization layer: a case study of collaborative downloads in VANETs

Current approaches to Cloud-based Mobile Augmentation (CMA) leverage (cloud-based) resources to meet the requirements of rich mobile applications, so that a terminal (the so-called application node or AppN) can borrow resources lent by a set of collaborator nodes (CNs). In the most sophisticated approaches proposed for vehicular scenarios, the collaborators are nearby vehicles that must remain together near the application node because the augmentation service is interrupted when they move apart. This leads to disruption in the execution of the applications and consequently impoverishes the mobile users’ experience. This paper describes a CMA approach that is able to restore the augmentation service transparently when AppNs and CNs separate. The functioning is illustrated by a NaaS model where the AppNs access web contents that are collaboratively downloaded by a set of CNs, exploiting both roadside units and opportunistic networking. The performance of the resulting approach has been evaluated via simulations, achieving promising results in terms of number of downloads, average download times, and network overheadMinisterio de Educación y Ciencia | Ref. TIN2017-87604-

COYUNTURA ECONÓMICA, año 2, núm. 2, enero-abril 2020

La pandemia que atraviesa el mundo a causa del virus SARS-CoV-2 ha generado grandes cambios a escala mundial y en distintos ámbitos de la humanidad. No solo por la cuestión medico biológica, la cual nos ha impuesto, como humanidad, el reto de controlar la epidemia, sino por la crisis generada por los disminuidos sistemas de atención médica y seguridad social, y la parálisis de la economía debido a las acciones de distanciamiento social, que nos llevan a plantear si el modelo económico neoliberal —que privilegia la explotación de los recursos naturales (la principal causa de la pandemia), por encima del aprovechamiento sustentable, el negocio de la salud sobre el derecho a la misma, así como la precarización del trabajo sobre los derechos laborales— es adecuado o debemos cambiar de paradigma en este sentido. En materia económica, la actual crisis trajo la primera recesión por diseño en la historia, ya que al tratar de contener la pandemia, los gobiernos cerraron sus economías, lo que llevó a una parálisis de la producción en la mayoría de los sectores y a la disminución del consumo de varios tipos de bienes. Además, dadas sus características, la actual es una crisis económica que viene tanto del lado de la oferta (ya que la mayoría de las empresas y negocios tuvo que cerrar de manera parcial o total sus operaciones, lo cual afectó principalmente al sector de servicios y a los sectores ligados a las cadenas globales de producción) como de la demanda (al dejar de consumir ciertos bienes no indispensables, cambiar hábitos de consumo por la reducción de la movilidad, así como al afectar el ingreso de los hogares tanto por la caída de la actividad económica como con el aumento de recursos a través de programas sociales).

Manejo pre, intra y pos-quirúrgico de dos caninos cardiópatas con fibrilación atrial

Las enfermedades cardiovasculares disparan mecanismos compensatorios fisiológicos y neurohumorales que modifican la función cardíaca y pulmonar, influyendo en los efectos de la anestesia. Sumado a esto, todos los agentes anestésicos deprimen la función cardiovascular directa o indirectamente. No existe un protocolo anestésico único e ideal para todos los pacientes con enfermedad cardíaca. El objetivo de este trabajo es presentar el manejo pre, intra y pos quirúrgico de dos pacientes con insuficiencia cardíaca congestiva compensada y fibrilación atrial sometidos a cirugía menor, no cardíaca.Facultad de Ciencias Veterinaria